First litho in a while

Gallery for images of work cut using PhotoVCarve
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Xxray
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First litho in a while

Post by Xxray »

Haven't done a litho in months, miss them.

This is an 8x8, features my cousin and her mother who recently passed away, just the sweetest lady ever. She lives across the country and I felt really bad not being able to make the services so I'm going to mail this to her as a surprise.

Turned out really nice, used a 1/32 tapered ballnose as usual with a 14% line spacing - Took nearly 5 hours but the quality is worth it, it has details right down to individual strands of hair. Can't see it but instead of my usual painted MDF I made the box out of walnut to add a little class.
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Re: First litho in a while

Post by dwilli9013 »

That is super nice. Love the detail. I have done many litho's on a 3d printer and let me tell you that rivals the quality I get.
She is sure to love this.
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Re: First litho in a while

Post by Xxray »

Pic is slightly blurry, is actually crystal clear looks just like a big lit up picture.
With the deep white in the lines on the shirt & hair I was worried it might punch through so I was conservative on depth [.20 and the blank is .24] ,,, But then I just did a few passes through a drum sander on the back to thin it down - Better safe than sorry with a 5 hr cut.

How long would it take to print an 8x8 ?
Doug

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Re: First litho in a while

Post by dwilli9013 »

Xxray wrote:Pic is slightly blurry, is actually crystal clear looks just like a big lit up picture.
With the deep white in the lines on the shirt & hair I was worried it might punch through so I was conservative on depth [.20 and the blank is .24] ,,, But then I just did a few passes through a drum sander on the back to thin it down - Better safe than sorry with a 5 hr cut.

How long would it take to print an 8x8 ?
To get that kind of quality I would run a bit slower so I would come out at about 6 hours total print time. I have a little trick I do on my printer that allows me to do a quality check while printing. I run two LED strips along the side of my print bed which illuminates the litho while printing. Kind of weird to watch it grow out of the print bed but it gives good indication of any problems during the print. What is your material?
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Re: First litho in a while

Post by Beltramidave »

Xxray,

Looks great!!

Can you tell me how you build your light box and what components that you use? If you have posted this already, can you point me to it.

I did my first litho recently, hoping to make it into a Xmas ornament and back light it from one of the tree lights...
https://www.dropbox.com/s/9urhlesmr5vyg ... R.jpg?dl=0

Thanks,
Dave
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Re: First litho in a while

Post by Jane Ndungu »

Hi Xxray,
That is very beautiful and classic work.
Could you kindly share material used? this was done with PVC?
Bought the software and have never had any success with it.
May be for africans settings are totally different since i always try with the examples given on the forum.


Regards Jane.

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Re: First litho in a while

Post by Xxray »

Material is Candlestone, which is a corian alternative. I use both, candlestone seems to have a little more clarity, but another set of eyeballs may differ.
Both are available on ebay precut - I had a guy that was selling it real cheap, I'll post the info if I can find it.

Box is pretty easy, you can get as intricate or simple as you like. I usually use mdf and paint it, but occasionally like this one I'll use a premium wood for elegance.
Box is just 4 2.5 wide slats joined together with air staples. There is a formula that plays tricks with the mind [my mind at least] ... If your project is 8x8" and you are using .5 material, the 2 side slats must be a total of 1" longer in order to cover up the top and bottom slats. I use a table router to rout in a .25 slot in each slat, .25 deep, the corian will rest in and be secured by this these slots, and it will all join together perfectly.
So the formula would be 8+1", then - .5 to account for the drop in the slots, so it would be 8.5 for the sides. Top and bottom, you want it to come just to the edges of the blank to meet up with the sides, but once again you have to account for the drop in the slots, so it would be 8 - .5, they should be 7.5 each.
Doesn't always work perfectly but the corian itself can be adjusted via table saw to make it perfect, assuming you are under and not over in which case you'd have to cut new slats.

When everything is dry fitted correctly I use air staples to join them together with the blank trapped inside, 2 in each corner. Of course, you could use glue and clamp it overnight, or use any number of joinery methods to accomplish the same thing, but the staples work great, are quick and barely noticeable.

The back is nothing fancy, just .25 mdf cut to size and painted black on the outside.

for the lighting itself you will need a soldering iron, LED strip, controller and plug, also plug receptacle. I hesitate to post any source links and they most likely will not be valid in a few months, but all are necessary and all can be found on ebay ect as well.
I use plain white strips for these, no reason why multicolor could not be used, but I think most people would not care to see something like this green. I used to put the connector in the back, but now I put it on the side in case people want to hang them.

Note that I use hot glue to tack down the strip, I don't trust the sticky back LED to hold against gravity for any length of time.

Lighting itself is wide open to preference, incandescent/fluorescent can be used. Using just a lightbulb though you would have to think about light distribution and possibly heat buildup ,,, But there is no reason why you have to use LEDS, though I think for this purpose they are far superior to anything else.

here are a few pics and a link to an older thread with much the same topic, sorry if they are sideways I am getting sick and tired of rotating pics.

http://forum.vectric.com/viewtopic.php? ... 68#p155568
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Re: First litho in a while

Post by Beltramidave »

Thank you very much for the detailed post.

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Re: First litho in a while

Post by martin54 »

Bought the software and have never had any success with it.
May be for africans settings are totally different since i always try with the examples given on the forum


Jane it's not quite as simple as using the same settings as someone else to achieve the same sort of results. There are still a lot of variables that need to be taken into account, every machine is slightly different so what works well for one persons machine doesn't necessarily work well for someone elses. You can however take the settings that someone else has used & then use those as a starting point for your own machine, there is generally a lot of trial & error involved in setting things up properly for your own machine :lol: :lol: :lol:

You will also find (well I did :lol: ) that it's much harder to get good results in wood than it is to get good results in something like corian.

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Re: First litho in a while

Post by Xxray »

Never tried a wood litho, on my bucket list.

It is important to measure material with calipers, just because it says it is .25 does not mean it is, thickness measurements like these are nominal.
Most often I find it slightly under, and thats very important dealing with thin margins. The idea really is to cut the whites as thin as possible without busting through.
Don't go deep enough and the whole thing will look drab, go too deep and you've ruined the project with no hope of fixing it [ask me how I know that]. Risky for me is .22 max depth on .25 material, conservative would be .21 ,, And these tiny margins can make a huge difference. All of this depends on a perfectly level working surface and perfectly accurate Z measurements, 0 margin for error.

I have the luxury of a drum sander, if I don't cut deep enough I can just sand the back until it it thick to my satisfaction.
Same thing can be done with other sanders, orbital, mouse ect, just take alot more time.
Doug

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Re: First litho in a while

Post by Xxray »

2nd litho in a while, so close but no cigar.

This young lady and her son lost their lives in a tragic highway incident, am making this as a surprise for her father, who I don't even know [he is a poster on another forum and he made a bunch of wood toy boxes to give away in memory of them, 1 of this pics he posted had an engraved plaque with her name so I googled it up and learned the sad details]. So I pm'ed him and said I made something special and requested an address, hope he doesn't think I am weird.

Anyhow, this was so close to greatness, but has 2 major flaws.
Worse in the line, have no idea what caused it, lost steps ? Shifting work piece ? Who knows, has happened to me before but is pretty rare. Line itself could be sanded out, but everything on the other side of the line is slightly darker due to depth, and nothing can be done about that, particularly since it goes right through the boys face.
As you can tell, I used a 45 line angle for this project, no special reason.

Other flaw is the bit busted through in upper right corner. Weird dark object on top is just my thumb.
5.5 hr cut but have no choice but to try it again, will probably send the father the reject as well, wish me luck. I may try to mess with contrast to make the blacks a little lighter and the whites a little darker ,,, As far as the line, thats in the lap of the gods as I have no clue what caused it.
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Re: First litho in a while

Post by David Brunson »

How do you get the contrasting colors?

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Re: First litho in a while

Post by mtylerfl »

David Brunson wrote:How do you get the contrasting colors?
The contrasting "colors" (not really colors, of course) happen automatically, based on the shades of the greyscale version of the bitmap used. The lighter the shades in the bitmap, the deeper the carve to allow more light to show through. The darker the shade, the shallower the cut.

The reason the blow-though happened in the corner of Xxray's example, is a combination of the depth of cut set as well as the brightness of the white. Two things can prevent this...don't have any totally bright white areas on the bitmap and/or don't make the cut as deep overall. Editing the bitmap in a photo editor allows complete control of brightness/contrast shade levels of the bitmap before importing into the Vectric software.

Lines in a litho are typically caused by some of the solid surface material become trapped under the bit during the carving process. Regularly blowing compressed air over the material can prevent this, but who has hours to kill sitting there blowing the material off during the carve? So, it just happens sometimes. If I were doing this on a super regular basis, I would consider setting up a fan or other directed airflow to do this automatically.

On 0.25"-thick material, I try to set the depth so that no area of the carve will cut deeper than 0.170" to 0.180". This leaves enough material behind so the lithophane isn't too fragile overall. Some folks carve deeper to achieve a brighter result when lit from behind and deal with the fragility - it's a personal choice.

The rotary litho shown below had cuts no deeper than 0.170" at the lightest areas and is lit by a single puck light with dim and bright settings. It lights up well on either setting, but the photo below is on the "bright" setting. The PVC pipe wall that this was carved from had a wall thickness of 0.25"
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Re: First litho in a while

Post by VE5MDH »

Wow, thanks for sharing this most beautiful work with us, Michael! I'm just flabbergasted that no one else has posted a comment towards your Mona Lisa!

Have you previously shared your process on how to work your PVC on a rotary spindle elsewhere in the Forums? (I figure the PVC must be vised in place, and slowly rotated via a Y Axis Stepper Motor some how?) Just a shear guess here!

I'd really like to learn this one!

BTW, I have yet to receive our Shapeoko3 in! (Departed Toronto earlier this morning)...

Just fabulous work!

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Re: First litho in a while

Post by Xxray »

David Brunson wrote:How do you get the contrasting colors?
To expand [or despand] on what Mike said, there are only 2 colors, black and white. But there are many levels of black and white, and the variety comes exclusively from how deep or shallow the cut is. Deeper cuts let more light pass and hence are brighter, shallower cuts pass less light and are darker. Pretty cool concept, artists have been doing lithos for centuries and it is only fairly recently that the process became automated. [These can actually be colored if you have the inclination, time and talent to do it]

The object of any litho IMO is to cut as deep as possible to allow the brightest colors to pass the most light, but it is risky. Cut too deep and you bust through, like I did. Not deep enough and the whole thing will look washed out. I go about .22 on a .25 workpeice, but this leaves nearly 0 margin for error, you had better be perfectly level, better make sure the workpeice actually is .25, and make sure you zero Z precisely. As Mike said, risks can also be reduced to a degree by manipulating contrast in the photo before you even start.

Another option would be to go .2 to leave a little more slack, and if its washed out simply sand down the back to make it thinner.
Doug

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